Automatic stop fob phonogbaph-motobs



J. T. SIBLEY. l AUTOMATIC STOP FOB PHONOGRAFH MOTORS.

APPLICATION FILED AUGJ |917.

L (7g mVENToR.

Patented 119.116,1919.

' BY 06,014 JWLATORNEY l Phonograph-Motors, set forth in the Vfollow- Y the longer records, it is necessary to vide means for adjusting the point at W ch ennuis T. SIBLEY` or NEWARK, .NEW JERSEY.

Aurom'rrc svror For. PHoNoGEArH-'Morons Specification of Letters Patent. Y Patetedlbec. 16, 1919.

Application led August 17, 1917. Serial No. 186,665.

To aZZ 'whom z't may concern:

Be i known that I, JAMES T. SmLEY, a citizen of the United States, residing in the cit ogf Newark, county of Essex, and State of ew Jersey, have invented a new and useful Improvement in Automatic Stops for ing-specification.

my prior application, Ser. No. 179,365, filed July 9th, 1917, I have illustrated and described an improved stop device, which serves to break the circuit, whenever the tone arm is swung clear of the record and released, so as to cut off the power of the electric motor which drives the turntable. My present improvement embodies all'of the essential features of said application, and has in addition thereto, means for stopping the motor by cuttingoff the current supply to the motor upon the completion of the record. Since the record groove varies in length, and terminates nearer the center, for

the circuit is broken, so that when and vonly when the record has been entirely completed, the circuit shall be broken and the motor consequently stopped.

` I The particular formof motor to which my present improvement is specifically adapted is illustrated in my pr1or` appllca- 'ti0n,ser.N0.175,565,1ed Jun '19th,1917.

The mechanism which I employ to accomplish this result is illustrated in the accompanying drawing and described in the following specication.

Figure 1, is a planview of so much of a tone arm as is necessary to show my improvement connected therewith.

Fig. 2, isa vertical section on line 2 2 of Fig. 1.

Fig. 3, is a rear elevation of the tone arm slowingmy adjustable circuit breaker in p ace.

Fig. 4, is a lan view of a part ofthe circuit reaker detached.

Fig. 5, isa section on line 5 5 of Fig. 3.

Fig. 6, is a fractional front view of the base of the 4tone arm.

Fig. 7 illustrates the tonearm.

Similar reference numeralsrefer to like parts throughout the specification and draw- The fixed base 1, ofthe tone arm is secured tothe phonograph cabinet by the screws 2, in

. the usual manner, through the flange 3. The

base 1, is Iprovided with the two circumferential grooves 4, 5, u on its inner face, Which serve as raceways or the lballs 6,7. The cap socket 8, having the two apertures 9, 10, is provided in the outer side of the base for the introduction of the balls into the raceways, and the cap 11, held in place bythe screws 12, prevents the escape of the ba1ls.----

The swinging tonearm 13, is in all respects like the tonearm of my 'rior application, Ser. No. 179,365, except fp r the connection with the base 1. The vertical end of the tone-arm 13, is reduced as at 14,' for insertion into the base 1, and is provided with the circumferential grooves 15,16, which register with the grooves. 4, 5, and receive the balls 6, 7. When coupled together, with the balls in their respective raceways and the cap 11, secured in place, the tone-arm 13, is locked to the base 1, but free to swing in a horizontal plane, with a minimum of resist- -end of which is supported by and .slides in the apertured bracket 19', .upon the under A side of the tonearm; I have deemed it unnecessary to describel it further than to say that .it reciprocates in the apertures 17 18, under the inliuence of the spring 2,0, upon raising the pivoted sound box section 13 of the tone-arm, and therebyY withdrawing the arm 51 from engagement with'the end of the rod 19.- Upon the-end of therodv19,

I secure the downwardly projectin contact pin 21, by means of the adjusta le connecting piece l22. Rigldly secured to the `VA'base 1, but insulated therefrom, is the metal connecting strip 23, .bent into the arc of a circle concentric withv the said base. Upon the strip 23, II mount the sliding connector 24, providing the same with a groove to fit the strip 23. In order to provide a comparatively firm frictional elglgagement between the strip 23, and connector 24, I

secure to the connector 24, the spring metal strap 25, by means of the screws 26, through the lateral projections 27. The strap is extended, as shown, to form the handle 28, by which the connector may be manually operated; the other end of the strap is cambered, as at.29, to hear upon the face of the strip 23,' in order to offer frictional resistance to the movement of the connector 24. When properly adjusted, the strip 23, and

connector 24, are in position for contact with the downwardly projecting pin 21, and upon the 4normal swinging of thev tonearm 13, during the playing of a record, this contact is maintained by the action of the spring 20.

Upon the upper part of the connector 24, is the inclined cam 30, the higher portion of which is made up of an insert of insulation, as 31. Adjacent to the highest point Y of the cam is the projection 32, through the-stud l insert a small stop pin 36, A

in the adjustable connecting piece 22, to engage the side of the tone-arm 13, so that while the spring 20, insures contact between the pin 21, and the connector 24,-or the strip 23, yet such contact is broken at some interval before' the pin can reach the stud 35.

1n F ig. 1, l have shown a simple wiring diagram to include the pin 21, and connector strip 23. The motor is indicated at 37, and the battery or4 other electric source, at 38. rlhe strip 23, is connected by the 'wire 39, through the batteryA 33, thence to the motor 37 from which a wire 40 leads to the base l1, which in turn is connected by the wire 41, to the rod 19.

I prefer to lead the wire 41 to the rod 19, rather than to ground it alone upon the base 1, for the reason that the balls 6, 7, do not form a good path for the current. 1n practice, l have found the balls scarred by electrolysis, when they are utilized as a part of the circuit, with a consequent deterioration of the bearingu The circuit is completed whenever the pin 21, bears upon the metal of the strip 23, or the connector 24, but is broken when said pin rides upon the insulating insert 31.

1n practice, the tone-arm 13, is swung to the eXtreme right, to insure engagement of the pin 21, with the stud 35 and consequent movement of the connector 24, to its extreme left hand position upon the strip 23. rlhe tone-arm is then moved to the left until the stylus needle of the sound box upon the tone-,arm isiminediately above the innermost record groove. 1n this movement, the pin 21, will ride up on the cam 30, and its insert 31, untilit engages the insulating point 34, of the screw 33. Further movement of the arm 13, will move the connector 24 upon the strip 23, so that 'macello when the stylus is at the inner record groove, the pin 2l, will have properly adjusted the connector 24, upon the strip 23. The tone-arm and sound box may then be adjusted to playing position and when the stylus needle is lowered upon the record, the spring 2 0, will bring the pin 21, in proper contact with the connector 24, and strip 23. When the stylus needle has traversed the record to its innermost groove, the pin 21, will have ridden upon the cam 30, to and upon the insulating insert 31, which of course willsbreak the'electric circuit through the motor, and consequently stop itg 1t is understood that when the tone-arm 13, is swung to the extreme right and the free sectional end thereof released and drops below the record, the rod 19, will be moved endwise by contact with the arm 51 to carry the pin 21, :tree from contact with the connector 24, and strip 23. This operation however is fully described in my above named prior application, and forms no part of my present application.

With my present improvement in connection with the motor of my prior application Ser. No. 17 5,565, no other stopping or starting mechanism is necessary or desirable, since the motor is started by placing the sound box in playing position upon the record, and it automatically stops either at the completion of the record or upon swinging the tone-arm to the eXtreme right and releasing the sound box, as described in application Ser. No. 179,365.

llt is obvious that many changes in proportion or dimensions of parts may be made without departing from the spirit and scope or my improvement.

'Ehe adjusting screw 33, maybe set so as ico to permit the phonograph turntable to rotate by its own momen-tuin to carry the soundboX stylus over two, three or even more of the last record grooves, independent of the-motor, and after the circuit has 'been broken, this will be readily understood from a reference to my motor application Ser. No. 175,565, above referred to.

l cla-ini:

1. in a stop device Jfor phonograph motors, the combination or a swinging tone-arm, of a contact pin yieldingly mounted upon said normal engagement with said pin, and adjustable means upon said strip for breaking .tone-arm, a xed contact strip mounted for l said engagement at any predetermined point in the swing of said tone-arm.

3. In a stop device for phonograph motors, the combination of a swinging tone-arm and a support therefor, with a contact strip upon but insulated from said support, a Contact pin upon said tone-arm for normal engagement with said strip, a sliding connector upon said strip, said connector having means thereon for engagement With said pin at each end of the swing of said'tone-arm to adjust the position of said connector upon said strip.

4. In a stop device for phonograph motors, the combination of a contact strip, a moving Contact pin carried by the phonograph tone arm in normal sliding engagement with said strip', and means for breaking said engagement at any predetermined point, cornprising a connector slidably mounted upon said strip whereby the position of said connector upon said strip may be adjusted, said connector having insulating projections at each end thereof in the path of and for engagement With said moving pin, and a cam upon said connector adjacent to one of said projections for lifting said pin free from said strip.

5. In a phonograph stop device, the combination of a swinging tone-arm and the support therefor,'a contact strip lupon but insulated from said support, a contact pin upon said tone-arm for sliding engagement with said strip, and an adjustable insulating cam upon said strip for breaking said engagement at a predetermined point.

6. In a phonograph stop device, the combination of a swinging tone-arm and a fixed support therefor,'a contact strip upon but insulated from said support, a contact pin upon said tone-arm for sliding engagement with said strip, and means carried by said -strip for breaking said engagement at any predetermined point. l

7. In a phonograph stop device, the combination of a swinging tone-arm and a`fiXed support therefor, a Contact strip mounted upon said support, a contact pin upon said tone-arm for sliding engagement With said strip, a sliding connectorupon said strip having stop projections'thereon in the path of and for engagement with said pin at each end of the swing ofsaid tone-arm to adjust said connector upon said strip, and a cam upon said connector in the path of said pin Y to engage the same and break .the engagement of said pin with said strip.

JAMES T. SIBLEY. 

